Centric indicator



Feb. 27, 1951 D. c. SHAPIRO CENTRIC INDICATOR Filed Aug. 29, 1950 INVENTOR. @wz'df W Patentecl Feb. 2 7, 1951 UNITED STATES ATENT OFFICE CENTRIC INDICATOR Application August 29, 1950, Serial N 0. 182,086

2 Claims.

My invention relates to new and useful improvements in dental instruments and is directed more particularly to the provision of a centric indicator device which is adapted for use by a dentist to detect the proper bite relation of the upper and lower jaws of a dental patient in making an impression on a bite-taking material in the process of fitting the patient with artificial teeth and to improvements in the means for obtainin the indications.

That is to say, I provide a device which permits the establishment of correct centric, or the correct relation of the jaws in connection with their functioning with artificial teeth. As is well known, dental patients often do not take a proper bite so that dentists fail to determine the proper relation between the upper and lower jaws. As the result of this kind of false bite, the denture or dentures often do not fit properly causing dissatisfaction and discomfort for the patient.

My device provides an accurate indication as to whether or not a patients bite is properly centered and a positive means for determining when correct centric has been attained by the making of an impression by the patient on biteblocks or other bite-taking material. Thereby is provided a means where a variety of indications are attained so as to dictate the corrections necessary to be made in order to obtain a perfect occlusion.

It is the principal object of my invention to provide a novel and improved construction of the type in which an indicating means is actuated by the contraction of the temporal muscles of the patient being treated whereby is provided an accurate indication of the correct bite of such patient.

There is the further provision of adjustable members whereby the same device may be adjustably mounted upon the head of any patient regardless of the size of his head so as to position correctly relative thereto the indicator actuating means employed therein at the desired points of intimate contact, all of which features of construction eliminate the now present objectionable inconveniences and provide a device which is operable with a maximum amount of ease and a minimum degree of effort.

One of the primary purposes of my invention is to provide structural and operational improvements in devices of the class to which reference has been made, which improvements not only simplify the structure as such, but also provide important, distinct advantages in strength, durability and the like.

With the above primary object in view, it is another object of my invention to provide a construction of the above described character in which the number of operating parts is greatly reduced and which is compact in accordance with the demands and desires of manufacturers and purchasers alike and which is not only distinctive in its appearance and practical in its value but also reliable in its operation and efficient in its use.

It is another object of my invention to provide a device for determining the attainment of a properly centered bite by a patient making an impression on a bite taking material, which device operates in response to the flexing of the templar muscles of a patient whereby a properly centered bite gives a positive indication, the device having means for indicating to the dentist when a properly centered bite has been attained, and serving to eliminate the guesswork and reduce the amount of time required, not to mention the cost involved, in obtaining a correct impression of the F which are adapted to be readily assembled and which when once assembled are positively and securely retained in operative relationship .and which cannot be readily separated from each other, either accidentally or otherwise.

Another object of my invention is to provide a device which has adjustably mounted electric switches having sensitive characteristics facilitating the closing of a circuit or circuits and thereby enabling the dentist to locate properly the actuating members of the switches in proper positions over the temporal muscles of the patient so as to be acted upon thereby.

Other prime objects of my invention include: first, the .securement of a higher degree of accuracy in' the manner of work performed therewith than has heretofore been possible with prior devices known in the art; second, the attainment of a higher speed of construction and assembly of a device of this character due to its simplification in design and it unique composition of parts; third, the attainment of a flexibility, or a capability of ready adjustment by which a large variety of work can be accomplished by means of the same device; fourth, the achievement of an ease in adjustments and repairs of the device due to its simplified form; fifth, the provision of an improved centric indicator construction which may be made more economically and with fewer operations in the manufacture of its parts, as well as in the assembly of the same, than prior devices known in the art; sixth, the provision of a construction which may be readily installed with respect to the various purposes for which it is intended; and seventh, the provision of such other improvements in and relating to centric indicator of the type above referred to as are hereinafter described and claimed.

My invention also consists in certain new and original features of construction and combination of parts hereinafter set forth and claimed in conjunction with the annexed drawings which illustrate a certain form of embodiment thereof, which form is deemed preferable and is a specific disclosure for the purpose of illustrating one embodiment of the invention by way of an example since the same has been found in practice to give satisfactory and reliable results, although it is to be understood that the various parts of which the invention consists, can be variously changed within the scope of the appended clairn without departing from the broad aspects and spirit of the invention and that the same is not limited to the precise arrangement and organization of the instrumentalities as herein shown and described.

All of the above cited objects I accomplish by means of such structure and relative arrangement of parts thereof, as will fully appear by a perusal of the description below and by various specific features which will be hereinafter set forth. To these above and other ends and with the foregoing various other and ancillary features and advantages and objects of my invention as will become more readily apparent as the description proceeds, my invention consists in certain novel features of construction and in the combination and arrangement of parts as will be hereinafter more particularly pointed out in the claims hereunto annexed and more fully described and referred to in connection with the accompanying drawings wherein:

Fig. 1 is a plan view of the device of my invention;

Fig. 2 is a front elevational view of one of the housings of my invention;

Fig. 3 is a sectional view through one of the housings;

Fig. 4 is an elevational view of one side of the housing shown in Fig. 3; and

Fig. 5 is a wiring diagram of the device of my invention.

Before proceeding, the importance of a clear understanding of anatomical structures and relationships in and adjacent to the oral cavit is obviously indispensable in the understanding of an invention relating thereto.

It is to be appreciated that in the art of oral prosthesis, in order to make a suitable denture, it is necessary to obtain the correct bite. The correct relation of the upper and lower jaws must be known in order that a correct occlusion may be obtained.

By the action of the muscles of mastication, the mandible or lower jaw is opened and closed and is moved forwardl and backwardly. The most important of these muscles are the temporal, masseter, external andinternal pterygoid, and buccinator muscles.

The temporal muscles, which are fan-shaped at their upper ends, are situated at the sides of the head. Each occupies the entire extent of the temporal fossa. The temporal muscle attaches to many bones of the head and face, but the main insertions, as pertaining. to dentistry, are

into the coronoid process of the mandible or lower jaw and the anterior border of the ramus of the mandible, this muscle arising from the temporal fossa.

The masseter muscle is short and thick and consists of two portions. The larger portion arises from the maxilla or upper jaw and is inserted into the lower half of the outer surface of the ramus. The smaller and deeper portion arises from the zygomatic arch and is inserted into the coronoid process of the mandible.

The external pterygoid muscle is short and thick and arises in two heads, the upper head from the greater wing of the shenoid or face bone and the lower head from the external pterygoid plate. Both heads are inserted into the condyloid process of the mandible.

The internal pterygoid muscle arises from the pterygoid fossa and is inserted into the inner,

side of the ramus.

The buccinator muscle occupies the interval between the jaws, crossing the temporal and masseter muscles. Its action contracts or sucks in and compresses the cheek.

The temporal, masseter and internal pterygoid muscles raise the mandible or lower jaw with great force. The external pterygoid muscle as sisis in opening the mouth, and its main action is to protrude the lower jaw. The lower jaw is retracted by portions of the temporal muscle.

When the patient bites correctly, the resulting contraction of the muscles of mastication in producing this action can be readily felt at the sides of the face and head. It is the contraction of these muscles which the instant invention contemplates making use of to actuate an indicating device so as to give an indication of whether or not a correct bite has been obtained. Such an actuation may be obtained at any of several points, as for example, adjacent the tempromandibular joint. There is no assurance, however, at most such points that a true indication will result, because of the interrelation of the several muscles of mastication above referred to. In other words, if an indication of a correct bite was sought at certain of such points, the movement of the lower jaw forwardly or backwardly while the mouth was open would result in an actuation of the indicating device so as to give a false indication.

The upper, fan-shaped end portion of the temporal muscle is only contracted, however, when a correct bite at that side of the jaws is obtained. This point of attachment or origin of the temporal muscle where it arises from the temporal fossa is consequently the best point at which to obtain an actuation of an indicating device to give a true indication of a correct bite.

In the following description and claims, various details will be identified by specific names for convenience. These names, however, are intended to be as generic in their application as the art will permit. Referring now to the drawing more in detail, in which similar characters of reference indicate corresponding parts in the several figures, and referring more particularly to the preferred form of my invention selected for illustrative purposes, I have shown a resilient metallic rear head band section It and an elastic front head band section [2 which are so related as to be embraceable around the head of a patient.

A pair .of housings M are provided although for purposes of disclosure only one of them will be discussed, they being similar in their design and function.

A rear bale l6 and a front bale 26 are pivoted at [5 to the housing l4 and each has upper and lower arms H and 2'! respectively and transverse ends [8 and 28 respectively connecting the upper and lower arms.

The rear bale [6 has a tubular stem 30 extending laterally from the transverse wall [8 through which wires may pass as will subsequently be described.

The outer free ends of the rear band section l have U-shaped clamps 32 secured thereto. Each clamp has relatively yieldable side arms 33 and apertures therein for receiving a stem 30. The arms are yieldable inwardly so as to release the stem and are inncrmally diverging relation as shown so as to grip the stem.

The elastic band section 12 is made up of two portions, l2 and 12'. The outer ends of the portions extend around the transverse ends 28 of the bales and are held secured back upon themselves by means of clips [3. The inner ends of the portions are adjustably securable to each other by means of a buckle 35.

As shown in Fig. 3, the housing has secured fast to its inner side a temple engaging plate 4!). Same is secured by means of a guide 4| receivable through an opening in a wall of the housing [4. A nut 4! is in threaded engagement with the outer end of the guide 4| and holds the member 48 in securement with the member 4!.

A switch actuator 42 is freely slidable axially of the member 4!! and is adapted to be actuated by the nerve in the patients head.

An adjusting screw member 44 having a manually engageable outer knob 46 is rotatably held in the outer wall of the housing 14 opposite 'from the temple engaging plate 4!]. A washer 48 is secured by any suitable manner to the screw member 45.

A U-shaped bracket 50 has a washer secured thereto and a threaded stem 45 of the screw 44 is threadedly engageable therewith.

A switch device 69 is secured in the bracket 50 by any suitable means such as screws 62.

The switch member may be any circuit closing device of the normally circuit open type. The device shown is a well known microswitch having a closing plunger 64 depressible for closing and making a circuit.

The end of the housing is closed by an end cap I4 and is preferably made from insulating material.

A visual indicator is provided and may comprise an electric bulb 12.

The cap I4 is provided with a socket 10 for receiving the bulb T2. The socket H3 securely holds a sleeve 74 to the end cap. The sleeve is closed by a bezel 78 extending thereinto which carries a lense 78 which may be of any desired color.

The socket 10 carries a pair of contacts 80 which are insulated from one another and are adapted for contact with the base and tip of the bulb I2.

The end cap 14' may be secured to the housing l4 by means of screws 82 as shown in Fig. 4.

The screw 44 moves the switch forwardly and rearwardly and is so arranged as to position the switch so that the actuator may close the switch as the switch is moved forwardly. As the switch is urged rearwardly. the switch is open, it being of the normally open type.

I have shown in Fig. a wiring diagram of the device of my invention. One side of the pair of switches 60 is connected by a connection 89 td.

a source of energy 92, such as a battery or the like.

The source of energy 92 is also connected by connections 9| and 9! to the bulbs 12.

The bulbs are connected to the switches by connections 95 and 95'.

The circuit closing switches 6i] control the electric circuits for the two signals. A lamp is in a circuit with its related switch and circuit closing member and the circuit may be traced from the source of electrical energy through the switch to the light and return to the source.

The source of energy 92 may be mounted on the device so as to be carried thereby or it may be located in any desired adjacent position in which case wiring may extend from the housing through the hollow stems 30.

If desired, energy may be supplied from the ordinary A. C. lighting circuit through voltage reducing means and may or may not be rectified.

The structure of the device having been explained, its operation will now be described.

The device is mounted on the patients head with the rear band section disposed at the rear of the patients head and the front band section disposed at the front of the patients head. So positioned, the temple engaging plates embrace or overlie the patients temples with the actuators disposed adjacent the templar muscles.

When the patients jaw is in proper centric position, the templar muscles on either side of r the head are expanded.

or bite, the mere flexing of the patients templar muscles will be suificient to close the switches and cause the lamps to become energized.

The lighting of the light indicates when a proper bite has been attained. The actuators being urged inwardly, the switches are closed when a proper bite has been attained.

The invention may be embodied in other specific forms without departing from the essential characteristics thereof. Hence, the present embodiinents are therefore to be considered in all respects merely as being illustrative and not as being restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all modifications and variations as fall within the meaning and purview and range or" equivalency of the appended claims are therefore intended to be embraced therein.

What it is desired to claim and secure by Letters Patent of the United States is:

1. The combination with a pair of signal de vices of a head band structure for holding the signal devices in contact with the temples at opposite sides or" the head comprising, pairs or" U-shaped members having spaced side arms, the side arms of each pair of said U-shaped members pivoted to the signal devices at opposite sides thereof on a common axis and the side arms oi each member of each pair extending in opposite directionsfiioin' the common axis, elongatedtmeznbers .vextending outwardly :from one ":member '01" the pairs thereof,:a resilient elongated band extending between said elongated .members, means carried byiopposite ends of said band frictionaliy and adjustably engaging said elongated me.:nher.;, and flexible adjustable .oand means having opposite ends connected to the other members .ofth'e pairs thereof.

2. A signal device of a centric indicator for contacting the templar muscle of a personszhead comprising, a housing having side Walls, a signal device on said housing, a temple member fixed to a side wall of said housing and having anouter face for engaging the head of .a person "adjacent thetemplar muscle, an operating'member slidable back and forth relative to said temple member on an axis disposed perpendicularlyrelative to the plane of the outer face thereof and having an outer end for engaging the templar muscle and an inner switch operating end disposed in said housing, a switch device for connecting in a MREFERENCES CITED The following references are-of record in the file 'ofthis'patent:

.UNITED STATES PATENTS Numb-er Name Date 611,391 Pike -Sept. 2'7, 1898 2',205;7'I5 H'en'cz June 25, 1940 20 2,331,669 Entriken Oct. 12,1943 23111194 Rome Nov. 19, 1946 

